My subfloor doesn't meet Kährs' criteria as it's hollowed. How can I rectify this?

The easiest way is to put several layers of cardboard underlay in the hollow, until you get an even transition. Also, if you're using plastic sheeting, make sure that the underlay is on top.
If it's underneath, it could become mouldy.

Can I lay my wood floor on top of a plastic/vinyl carpet?

In most cases, yes. Also, should the installation require plastic sheeting, it won't be necessary as a plastic carpet, in most cases, is even denser than sheeting. Just use a step noise reducing underlay directly on the carpet.

Can I lay my wood floor directly on a textile wall-to-wall carpet?

No. The only soft carpet that you can lay a wood floor on is needle felt carpet or similar hard material. If you lay a wood floor on a soft carpet, there's a risk that the glued joints will break; this is also the case with any subfloor that is too soft. NB: If the installation demands plastic sheeting, it must not be laid on top of an old carpet due to the risk of moulding. Also, consider the risk of dust mites in an old textile carpet. In most cases, you should rip up the carpet. If you're unsure, contact Kährs for advice. We're installing parquet in our living room, hallway and kitchen. All of the rooms are connected; can we lay the floor in one piece?

It's best to allow a movement gap in doorways between different areas, to ensure that the joint won't open. When you lay a floor through a doorway, there's a very limited length of joint to hold together a larger floor area on the other side of the wall. If you use a T-moulding between rooms, you eliminate the risk of "gapping" and create a neat transition.

Also, we do recommend that you give halls and kitchens floors an extra coat of lacquer after installation. By dividing the floor, you'll create a natural border between the re-coated floor and the remaining area.

Does it matter which glue I use to install a traditional tongue and groove floor?

Yes. In recent years, we've carried out an extensive study of PVAc glues and superior products can be up to 3-4 times stronger. All Kährs adhesives are superior and ensure a good installation. Quality adhesive is especially important if you're installing over underfloor heating, where the stresses are greater.

Should I glue floors with the Woodloc® joint?

In most cases, floors with the Woodloc® joint shouldn't be glued. However, if you have to file off parts of the joint, e.g., when you end the installation against a door, some adhesive might be necessary. Can I install a wood floor over an underfloor heating system?

Yes, the two products go hand-in-hand. However, certain points should be considered: The surface temperature of the finished floor must never exceed 27°C, in any area. Preferably, use a 15 mm multi layer parquet or Kährs Linnea which is 7mm thick.

Also, bear in mind that Hard Maple and Beech expand and contract more than other species, which increases the risk of gaps between the boards.

Should I use plastic sheeting with underfloor heating?

Yes, you should always use plastic sheeting with underfloor heating, regardless of the type of sub-floor and age of the joists. The plastic sheeting protects the floor against the moisture that is always present in joists.

When the heating is switched on, the moisture is driven against the surface of the floor by the vapour pressure. Without plastic sheeting, the moisture migrates up into the wear layer of the parquet floor and is trapped under the lacquer pre-finish. This can result in moisture damage.